1. Field of the Invention
The present invention relates to a joint type disc cage of a roller bearing, in which a joint means is provided at a sheared part of the disc cage so as to fit it into a single-pieced outer or inner race of the roller bearing.
2. Description of the Prior Art
In the conventional roller bearings, the rollers are arranged at uniform intervals, and in order to improve the rolling action of them, a disc cage with a plurality of roller accommodating slots formed therein is installed on the outer or inner race of the roller bearing.
In the case where the inner or outer race of the roller bearing is divided into two pieces, a circular disc cage which has no sheared part but is continuous is installed.
However, if the inner or outer race of the roller bearing is completely circular without a sheared part, then the disc cage cannot be installed into a installing groove of the inner or outer race.
Therefore, in this case, the disc cage is sheared in the radial direction into two pieces, and then, the two pieces of the disc cage are assembled to the inner or outer race of the roller bearing.
Alternatively, the disc cage is sheared into a C shape, and the sheared part is spread to expand the inside diameter of the disc cage so as to assemble the disc cage into the installing groove of the inner race of the roller bearing, or vice versa. This prior art was patented by the present inventor under the Korean Utility Model Registration No. 158987 (dated Jul. 20, 1999) and No. 158988 (dated Jul. 20, 1999).
In this disc cage, in order to install a single-pieced disc cage into the installing groove of a single-pieced inner or outer race of the roller bearing, a circular disc cage is sheared into a C shape. Thus if the C shaped disc cage is to be installed into the installing groove of a single-pieced outer race, the disc cage is compressed to reduce the outside diameter of the disc cage, thereby inserting the compressed disc cage into the installing groove of the outer race. On the other hand, if the C shaped disc cage is to be installed into the annular installing groove of a single-pieced inner race, then the C shaped disc cage is spread to expand the inside diameter of the disc cage, thereby inserting the disc cage into the annular installing groove of the inner race of the roller bearing.
Once being installed, the compressed or spread disc cage is restored to the circular shape owing to the self elasticity of the disc cage. In this case, a small gap remains at the sheared part of the disc cage.
Under this condition, the ends of the sheared part of the disc cage are facing toward each other, but there is no mutual engagement. Therefore, when the rollers of the roller bearing revolve at a high speed under a heavy load of the shaft, the ends of the sheared part of the disc cage collide together due to external pressures or impacts, or the disc cage generates severe friction-vibrations. Therefore, the end portions of the sheared part of the disc cage are materially degraded or deformed. Consequently, the end portions of the sheared part of the disc cage undergo corrosions and abrasions, with the result that the performance and the stability of the disc cage are deteriorated.
The present invention is intended to overcome the above described disadvantages of the conventional techniques.
Therefore, it is an object of the present invention to provide a joint type disc cage of a roller bearing, in which a joint means is provided on the sheared end portions of the disc cage, thereby making it possible to maintain the characteristics of the non-sheared disc cage.
It is another object of the present invention to provide a joint type disc cage of a roller bearing, in which owing to the joint structure of the sheared part of the disc cage, the installation of the disc cage can be easily carried out, and the installed disc cage is maintained in a circular form, so that the function of the disc cage becomes superior, and deformations, abrasions and degradations of the disc cage can be prevented, as well as ensuring the durability and safety of the roller bearing.
In achieving the above objects, the joint type disc cage of a roller bearing, the disc cage being circular and being sheared so as to install it into an annular installing groove of an inner or outer race of the roller bearing according to the present invention includes: joint end portions 2a and 2b (of a sheared part 2 of the disc cage) having a function of a joint to be firmly engaged together without being loosely moved to left or right or in a radial direction.
That is, in order to install a circular disc cage into an annular installing groove of a single-pieced inner or outer race of a roller bearing, the disc cage is sheared into a C shape. However, unlike the conventional sheared disc cage in which there is formed a small gap in the angular direction, the sheared part of the disc cage of the present invention is engagedly coupled to form a joint. In other words, the disc cage is sheared by a press-blanking, and the sheared line is curved without leaving any gap as if two hands are grasping together, thereby forming a joint type disc cage.
There are available various asymmetric joint contours such as a J type joint, an N type joint, a Q type joint and other geometric puzzle joints.
The joint type disc cage of the present invention is sheared at one place, and therefore, when it is to be installed into an annular installing groove of an outer race, the outside diameter of the disc cage is reduced by compressing the disc cage to install it into the annular installing groove. On the other hand, when the disc cage is to be installed into an annular installing groove of an inner race, the sheared disc cage is spread to expand the inside diameter of the disc cage to install it into the annular installing groove of the inner race.
After fitting the disc cage into the annular installing groove, a slight external force is applied to the joint end portions of the disc cage to engagedly couple the end portions of the disc cage, thereby making the installed disc cage completely circular. In this manner, the sheared disc cage is restored to the perfectly circular contour which had been maintained before shearing it. Thus when the roller bearing revolves under a heavy load, there exists no gap at the sheared part of the disc cage, but the sheared end portions are firmly engagedly coupled together, and therefore, any loose movements do not occur in the lateral or radial direction.
Therefore, there will be no apprehension that corrosion, deformation, abrasion and degradation may occur. Further, the disc cage can perfectly carry out the function of maintaining the rollers at uniform intervals, and the function of lubricating the rollers. Further, the durability and safety of the roller bearing can be improved.